Real-Time Simulation of VLF Atmospheric Noise for Use in the Calibration and Characterization of LORAN-C Receivers for Aircraft Navigation

Abstract

This paper describes a real-time simulation technique for generating realistic VLF band atmospheric noise. Noise in this band consists of a background Gaussian component plus a non-stationary impulsive component. The simulator implements as a real time simulation the theoretical model described in Feldman[1]. Stored channel simulation using a high performance personal computer (PC ) drives an off the shelf multi-channel signal generator, providing a high degree of sophistication at low cost. The simulator developed at the Volpe National Transportation Center has been used to characterize Loran-C receivers for use in aircraft navigation. Examples of use of the new simulator in the characteriza tion of Loran-C receivers are presented.

Keywords

LORAN-C real-time simulation noise simulation atmospheric noise aircraft navigation.

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References

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